This is playing nonstop on all local news channels in the Boston area, and the footage is terrifying. One house just blew up, and then residents across a wide area said they heard hissing in their home and fires broke out in 70 of them. A news helicopter circled one of them for 40 minutes before firefighters could reach it, there were just too many other fires and not enough local resources. One of the towns (Andover or North Andover) had 38 fires in all, including 18 burning at one time.

They have a good "mutual aid" system here and fire apparatus from the neighboring communities including New Hampshire and all over the Boston area eventually flooded in to these three cities (Lawrence, Andover, North Andover) to help.

Andover resident here. The local response has been super impressive. I've never seen so many emergency response vehicles and personnel mobilized so quickly from so many different places.

We drove north to New Hampshire on instinct as soon as we had a sense of what was happening (about an hour before the formal evacuation), and saw police and firetrucks heading south the entire way. After dinner, on our way back south (not home, but to another place to stay tonight), all the highway exits in the affected areas were closed, with police at each exit offering guidance to drivers who weren't sure what to do or where to go.

The affected communities are suburban -- not in the boonies, but not urban either, and definitely not used to having to respond so urgently to a widespread problem like this. They appear to have been very well trained and ready for it.

This is heartwarming to hear, and not surprising from my experience. Although people are great at minding their own matters in the greater Boston metro and beyond in non-crisis situations, when folks need help, this is a great place to get that help.

>Although people are great at minding their own matters in the greater Boston metro and beyond

No. They are very much are not. Massachusetts people are busybodies compared to people farther north. They very much care about things that others do that don't effect them. It's been this way since Boston was founded in the 1600s and it's deeply ingrained in the culture. I didn't notice it until I lived in northern New England for awhile.

What he means, I assume, is that Massachusetts people are very "cold" compared to people in the South or on the West Coast in the sense that strangers are very unlikely to greet you or chat you up. It always weirds me out when people start doing that but visitors to this area complain about the opposite.

Nobody will talk to you on the subway. Everybody will be very interested on whether your replacement garage door "fits the character of the neighborhood" though. If your kid gets off the bus and lets themselves into the house before you show up from work you are going to get really familiar with the local cops.

My favorite two anecdotes:

I once drove ~1/2mi home after getting a flat (in the tires' defense, it was older than me), mid-morning on a weekday. Less than 5min later, while I was in the middle of "screw these used pieces of shit, I'm ordering all new Firestones on Amazon" the cops, knocked on my door. Turns out someone had followed me home and then called me in to the cops as a possible drunk driver, on a weekday morning. And the cops were happy to oblige. They had no problem showing up and playing the questions game with me over a call they would have ignored in NH or ME.

Back when I was in middle school (decades ago) my parents got lectured by the school about how they were raising me because I kept getting in trouble for using pads of sticky notes to make short animations of car crashes, explosions, and other typical action movie stuff.

If those aren't hallmarks of a society that think's it's perfectly fine to get unnecessarily involved in someone else's problems then I don't know what is.

That seems like a phenomenon of upper-class neighborhoods. My neighbor has a roof with a bunch of missing shingles and has put a tarp instead of fixing it; I doubt anyone is that bothered what I do if it's not crazy.

> Back when I was in middle school (decades ago) my parents got lectured by the school about how they were raising me because I kept getting in trouble for using pads of sticky notes to make short animations of car crashes, explosions, and other typical action movie stuff.

You have to admit they were on to something though, here you are writing stuff on a forum for scary hackers.

I know someone from the area and she says the impression is Columbia Gas willfully ignored the situation in Lawrence, the poorer of the suburbs, than Andover and the more affluent adjacent towns. Accurate assessment?

You would need a overpressure relief valve, not a regulator. And it's not clear to me what you would do with the overpressure except either (a) block it to protect internal systems, leaving the externals to fend for themselves, or (b) flare it off via a rooftop vent system, which would be quite hazardous and unwieldy to maintain.

You already have 'your own' regulator. And it will be as good or better than anything that you are likely to install yourself. Also, having two regulators in series will kill your flow, they need a delta to work with.

If you own a house, you quickly become obsessive about all kinds of maintenance tasks to ward off disaster. And then whoops, one day someone over-pressurizes the gas line and there it all goes in a shower of flames anyway.

All I am going to say is: When those two idiots set off those pressure cooker bombs at the marathon, there was no lack of cops to form an army to shut down the entire city for nearly three days! Screw off, Boston!

I don’t know about the rest of the nation but the natural gas infrastructure in Massachusetts is comically terrible. It isn’t unusual to be walking down the street in Boston (note: a separate utility than tonight’s incident) and to walk into a cloud of natural gas. I had such a cloud on my residential street for years that was strong enough to burn your eyes. National Grid would come by every few months, stick a probe in the ground, and declare it not worth fixing despite our repeated calls. I wonder how much of their product actually makes it from production facilities to end households without leaking out along the way.

You might try looking up your gas company's agent for service of process (Secretary of State site search, probably).

Send a registered snail mail describing the leak in your neighborhood to the agent, copy corporate counsel and at least one local news organization. Major bonus points if you find and copy the gas company's insurance carrier. Emphasize the potential for destruction of property and death of innocents - and the gas company's potential liability. Raise the spectre of California's PG&E and San Bruno.

Management and its insurers care deeply about liability. Old-fashioned paper trails can be surprisingly effective.

> On January 13, 2012, an independent audit from the State of California issued a report stating that PG&E had illegally diverted over $100 million from a fund used for safety operations, and instead used it for executive compensation and bonuses.

It's like how it's best that some companies or probably even countries are best to stay away from nuclear power: to have even moderate safety requires a certain attitude and ability to organize. If your city or country has a lot of corruption, then it's really hard to have safety because companies get competitive advantage from bribing.

It's like being a ship on the ocean. You could be lulled into a false sense of safety by the pretty views and the flying fish but death is always right around the corner and waiting mercilessly for you to fuck up every so slightly.

We regularly have the fire department roll up in front of my house to investigate a reported gas leak. One time it scared the crap out of me as I went to let the dog out and there were men on my deck. As it turns out they were from the FD and checking out my grill

At some point I saw a map of all of those mini-leaks which are known and not worth fixing and sure enough one is right in front of my house

I believe there are several efforts, some of them community-driven, to identify and catalogue gas leaks in Massachusetts. Here's one with a fascinating (startling?) map of gas leak locations (scroll down): http://gasleaksclf.org/

Here in our Seattle bedroom community the gas people are phenomenal, and they deal with every leak, no matter how minor. They will come out in the middle of the night without being asked twice. I am thankful.

In SDG&E territory, I had a plumber notice a leak near the gas meter, and encourage me to call it in. I called it in at 3PM. At 5 there was an initial crew. At 11pm the guys with the real tools came and finished it off, including the use of a jackhammer at 12:30am (you do what you have to do). Then I read about people with gas bubbling up through their lawns in San Bruno before it blew up and I was shocked that the other utility company had such low standards.

I've never heard of "mini gas leaks" that are supposed to be fine until I've seen this thread. Every gas leak that's reported here must be fixed. Gas-related explosions still happen, I'd say it's 50:50 people messing with gas piping and people attempting suicide.

I did a project on this some time ago. Columbia gas was one of the worst offenders for sheer volume of leaks. Not only is it normal to leave leaks unfixed, frequently they disappear from the public record without any recorded nearby fixes.

It'd be interesting to see whether there's a correlation between explosion and leak location.

I'm in Michigan, with DTE Energy gas service. I had an experience a decade ago where they came to the door and informed me that the line needed to be replaced due to a leak. That made me pretty worried, but their nonchalant attitude seemed to indicate that it wasn't a big deal. Turns out (if I understood and remember it properly) that it was a small leak that was known about for some time—it was probably detected by a vehicle that drives around with sensors mapping out leaks.

Both that house and the one I own now are over 100 years old. The water, sewer, and gas lines are, AFAIK, original.

They are subsidiary of NiSource Inc. (NYSE:NI) a huge publicly traded utility. First time I've ever heard of something of this scale that I can remember. Gas explosions aren't unheard of but so many in a small area is perhaps unprecedented.

When i was growing up something similar happened in our town - over pressure caused by connecting a high pressure gas line to the local supply - police closed off the whole town and a few bits and pieces blew up/caught fire.

My initial thought in this case, before hearing about the underinvestment by the utility company, was SCADA kit tampering/hacking. Running the pressure slightly high would be a very similar approach to the spinning of centrifuges at slightly over speed - not immediately detectable but with serious consequences. Judging by the comments on this thread it looks more like ineptitude/negligence by the utility.

We forgot how insane it is to pump explosive gas into our houses beacause we’ve gotten so good at it. I was remembering a similar accident near me, and it turned out to be 1982. That’s a lot of unremarkable years in between.

(1982) A state of emergency was in effect today after 28 homes and businesses burst into flames within seconds when the pressure in a natural gas line was kicked up accidentally, causing water heaters and furnaces to spit fire like "blowtorches."

As much as I love my gas stove, part of me can't help but think that we mostly won't be running gas lines into new houses within a few decades. Both gas and electricity can kill you, but a closed pressurized system of flammable gas is just harder (and more expensive) to engineer, install, and maintain than a wire run. But now I'm curious as to what sort of huge increase in power generation capacity it would theoretically take to cover for what gas heating currently provides...

In the process of moving to renewable energy, The Netherlands has banned natural gas connections to new houses starting 1 July 2018. This is even though the country has one of the largest gas fields in the world [1]. Electric (induction) cooktops and district heating are very good alternatives to using gas (and safer, even though the gas infrastructure is very good).

Much like the biggest farm is not necessarily the most profitable, the Netherlands government reporting office claims peak production was a decade ago, and its all downhill until the mid 2020s (lets say, five years away?) when the Netherlands switches over permanently from being a net producer of natgas to being a net importer.

Kind of like how the UK peaked around the turn of the century and has been a net importer for more than a decade, but delayed by maybe 15 years.

In this line of business (IT) its all about scaling. The economic models around natgas are hilarious in that nobody scales beyond one, at least in public. So every country on the planet has a natgas economic model where on a scale factor of one, the permanent transition from exporter to importer is "no biggie" because there's an infinite supply of infinite cheap commodity natgas from world trade, so we'll just have some ... permanent inflation from printing money to import all that natgas. That economic model sounds really good scaled to one country, but doesn't work well when scaled to "pretty much every country on the planet at the same time and the global cheap commodity natgas market disappears".

Natural gas stoves used to give me the willies. Then one day the big bottom square heating element in my electric stove started making a weird noise. I opened the oven and looked at it for a minute and the thing exploded! In a million years I wouldn’t have thought it was possible.

Fortunately I didn’t get hit by any shrapnel. And I got a new oven out of it, which was nice. But now I’m afraid of both cooking methods.

We're living in the peak right now of natgas so its no surprise in a couple decades the general public will not be using natgas.

Discoveries peaked in the 70s, normal production peaked a decade ago, strange fracking experiments to squeeze the last blood from the rocks is peaking "around now ish".

Natgas is vastly more useful to make plastics and fertilizer than to run my clothes dryer, and global demand is completely unconstrained, and economic conditions such as income inequality, demographic changes, etc are only getting worse, so its not controversial at all to claim in a couple decades your average house will not have natgas service.

Generally its cheaper to install insulation and better windows than to install more electrical generating capacity. Probably cheaper to install insulation and a heat recovery ventilator than to install natgas fuel-cell cogeneration plants in each basement or triple the number of nuclear reactors.

I would imagine this ties into long term planning such as chopping maintenance budgets. If buried gas lines can't be maintained to any standard other than lasting the next 80 years at great expense, and corporate strategy indicates not enough end user consumers will be able to pay $2000/month inflation adjusted to heat their house in twenty years, then just pencil whip the maintenance until the service shuts down.

You can see the future of residential natgas in the past of dairy milk delivery, ice block delivery, to some extent postal service, land line phones, and cable TV. You can expect a lot of gas-lighting (oh the pun) about how the replacement services are so much better (solar heating, insulation, etc)

Here in the developing country where I live the locals think Americans are insane for doing this. When I first moved here I thought they were backward because there is no gas piped around. It's all portable refillable tanks that you buy at the corner shop and hook up to your stove. Seems like a recipe for disaster, right? Well yes, there are accidents and an explosion now and then. But it's limited to a single house in most cases. They don't have whole neighborhoods erupting due to failing infrastructure. So maybe I'm changing my mind and being less developed has some very real advantages.

The US is not unique here. I suspect you'd find that an even higher percentage of homes in the UK are connected to gas lines.

But these types of explosions are extremely rare, and most likely you'll find more accidents in less developed countries from people connecting the tanks incorrectly than you'll find from instances in the US, UK, or other countries of massive accidents like this one.

Yes it would, but part of that is that above a set pressure they can start venting.

The idea is that an increase in pressure relative to ambient will cause a needle (low flow) or disc (high flow) valve to open or close, pressure in the pipe higher than the desired delta will cause the valve to close and vice-versa.

The venting is a safety measure to protect downstream equipment in case of regulator failure (for instance, if it seizes too far open, or the seals are porous and the consumers are all not using gas which would slowly cause the pressure in the house side to rise to the same pressure as the feeder line), and normally this would be to let little bits of gas escape, but if the line pressure were high enough it would allow a constant stream of gas to escape from regulators that were 'borderline' or seized up. It could also cause the membrane under the spring to break, and that would let even more gas out through the seal between the tap stem and the regulator housing, and any consumers that were 'on' at the time would have to deal with the overpressure directly which they would not be designed for. They can handle a bit of overpressure but not for ever and not beyond certain set limits. Especially aluminum burner housings would simply burn up after some time.

In some lines there are burst plates as the final safety, those really should never go but when they do it is definitely a spectacle if there is an ignition source nearby. A burst place is a purposefully weakened structure that is bolted (with a seal) on top of a gasline so that when the pressure increases above the burst plate's rating the plate will rupture. This does not self reset for obvious reasons and will need an on-site technician to repair and would come with a serious investigation into what went wrong upstream.

There is also the opposite device, an emergency shutdown valve that automatically closes when the flow gets either too high or goes negative. The former to ensure that a ruptured pipe will not vent enormous quantities of explosive gas in to the atmosphere, the latter to avoid having an air/gas mixture in the lines.

Gas infrastructure is quite interesting, and very expensive to install and maintain.

Up to a point, yes. But fundamentally a regulator consists of a pipe in and a pipe out with a valve in the middle controlled by the downstream pressure. A high enough pressure in the input pipe can rupture the valve seals (which are rubber). Then the full pressure goes into the downstream pipe (which isn't rated for high pressure) and it leaks.

The system should have safety overpressure relief valves, but obviously something went wrong.

The over-pressure protection sits on the far side of the pressure reducer.

Imagine a tube that should be at 1.2 atm, and a feeder line that is at 5 atm. The equipment and the lines on the far side of the regulator may be able to deal with 3 but no more than that. If all the consumers are off and you do not bleed excess gas from the bypass leakage into the atmosphere the pressure on the far side will slowly increase until it is 5 atm, the pressure of the feeder line (no seal is perfect). So you need some way to get rid of that, and normally that is what the vent does, so it will allow miniscule amounts of gas to pass out in order to not let the far side go overpressure.

But if the feederline suddenly jumps to 10 atm, ruptures the seal or if the regulator sticks 'open' when that spike happens then the only thing that stops your internal line to go to that pressure is the bleeder (and in extreme cases, a burst plate that will break). This would allow a lot of gas to be released.

This is also why in some countries regulators are installed outside of the house rather than inside.

Another avenue for gas to escape if the seal breaks is the atmospheric port that allows the pressure of the chamber on the atmospheric side to be the same as ambient, in a sealed housing that would not be the case. Gas pressure regulation is not just about reduction, it is also to output a fixed delta relative to ambient otherwise your stove would make much larger flames if the atmospheric pressure was low!

Those regulators are works of art, totally passive and yet with a whole raft of features.

You have to remember that natgas is extremely old, like mid industrial revolution era. Homes had natgas before they had electricity, usually.

In the early days they billed on the number of gas jets for illumination but once gas stoves and furnaces became a thing they needed some way to measure, and there's some weird technology out there involving something like an archimedes screw sitting in a couple inches of anti-freeze driving low friction clockwork. Now a days its probably optical sensors instead of clockwork but whatever.

Two engineering topics are being missed; flow rate thru an orifice is strongly non-linear, and there are no hermetically sealed large scale transport technologies. Its staggeringly impressive that like 99% of electricity pumped into the grid makes it out the other end. Its not practical from an engineering standpoint to operate a leak free material transport pipeline. There's plenty of engineering guidelines such that a leak rate ten times lower than could theoretically cause an explosion is quite acceptable, until some idiot accidentally applies a 10x overpressure forcing open orifices permanently and increasing the leakage flow rate 200x and then kaboom.

Its kind of like automobile gas stations... it would be nice to never have a leak and LARP that we'll be very serious and studious about never having a petroleum leak, but that mindset leads to design and operations decisions which become environmental disasters when the inevitable happens. Better to build everything with the assumption the underground tank will leak one liter per month than to plan the leak rate will be zero. Also no level of idiot proofing is perfect; that leak-tolerant station design will still fail if some truck driver pumps 2000 gallons into a 1000 gallon tank while not paying attention.

There's also safety tolerance / clickbait issues. Natgas averages about ten customers dead per year in the USA. Its very difficult to get stats for in-house mis-adventure but it seems about three hundred die per year from in-home electrocution, so its kinda a rounding error. Food related illness (food poisoning leading to dehydration leading to death) kills about 5000 per year in the usa per google (which seems high?) so you're about 30 times more likely to electrocute yourself at home than die in a natgas explosion, and 500 times more likely to be killed by whats in your cooking pot than whats heating your cooking pot. Given that, more investment to prevent natgas deaths would likely result in more deaths from other causes; taking money away from "stop drinking corn syrup" or "cook meat to 165F" will kill more people than a 10% improvement in long term natgas death stats would save.

It does, but those will vent to the atmosphere, if there is enough overpressure and it lasts for long enough the amount of gas released would be considerable.

It seems one solution might be to have a small constantly-burning flame (the other posts here that say small gas leaks are basically being ignored suggest that it wouldn't really cost much more) at the relief valve exits, so that if they vent, the excess gas just gets burnt. Obviously the relief valve exits should be located away from flammables, and preferably visible so that extended overpressure events are immediately noticeable from the flames coming out:

> It seems one solution might be to have a small constantly-burning flame (the other posts here that say small gas leaks are basically being ignored suggest that it wouldn't really cost much more) at the relief valve exits, so that if they vent, the excess gas just gets burnt.

When the amounts are larger that is exactly how it is done. But for trace amounts the mixture would not reach a concentration level where it is combustible and then you need a whole setup around that to batch it to the point where it is.

In legacy “low pressure” systems, regulators aren’t used at the residential end at all. Our neighborhood was recently upgraded to a “high pressure” system, and regulators were introduced, along with vents cut through the foundation to the outdoors.

Our neighborhood was built in 1950. This system upgrade included replacing all the mains in the road as well.

I saw it mentioned elsewhere in this thread, but it may be worth noting that there has been a lockout of National Grid workers since June 25th. These workers serviced "700,000 gas customers in 85 communities in eastern Massachusetts", NGrid has replaced them with contract workers to continue service[0].

A site representing the union states that those locked out "do the critical work of maintaining natural gas lines for homes, schools, and businesses across Massachusetts"[1]

Unsure if this is related to the current incident & Columbia Gas

edit: Press conferences seem to indicate that Columbia Gas is responsible for this region and not National Grid. Seems Unrelated

I am wondering if Watch_Dogs-style cellphone-controlled terror might become reality soon if hackers manage to control gas companies' pressure systems; they could truly cause devastating blows to arbitrary cities with very little defense against and limited tracking back to perpetrators.

I hope this isn't an obvious question: Why aren't there safeties in the system to control these kinds of problems?

For example, I have a giant gas meter outside my home. How come it can't turn the gas off when the line is over pressure? Massachusetts state law requires that the gas company change it every few years. (I'm a MA resident)

Couple of thoughts about gas and electricity and the similarities and differences:

- an overpressure situation is specifically trying to blow through whatever "off" means (e.g. a ball valve or whatever the valves are). If the pressure rises too much, that valve is going to fail. That's true of circuit breakers too, but the "overvoltage fault voltage" of a circuit breaker is likely going to be way way way higher than anything you could reasonably expect from the grid, although lightning could probably flash over it.

- Your breaker box will turn off during certain forms of fault, but not all. A line overvoltage probably wouldn't trip a breaker until the line voltage gets high enough to cause a fault in some piece of equipment connected downstream of the breaker (e.g. it blows up a switching power supply in your house and that fault current trips the breaker)

- In the gas overpressure case, if all of the houses had gas meters that automatically turned off... the pressure in the community gas line would rise higher and higher. This is going to sound a bit cold, but it's likely better to have some houses blow up due to overpressure than to have a gas main explode after all of the houses have already shut off the gas.

Bad situation all around :(. While acknowledging that I'm not a Mech E, my guess would be that the best solution would be to have periodically-placed blow-off valves on the gas main that could flare the gas if there were an overpressure situation. You don't really want to just release it, because then you've got a cloud of gas floating around that could get ignited by... whatever random ignition source.

This is probably a stupid idea, (I know absolutely nothing about natural gas) but why can't we emergency vent the gas outside?

My gas meter is already outside the house, more than 30 feet away from anything flammable. In an emergency overpressure like this, shouldn't I be able to pull some sort of emergency lever to vent the gas outside.

Yeah, that gas is flammable, which is risky. But that has to be less risky than just sitting around waiting for my house to blow up, which seems to be my only option today.

If your gas installation is anything like mine, you could go outside and shut off the feed into your house. There's a valve that you could turn with a crescent wrench. Mine, at least, has a hole in it that the gas company can put a lock through when the valve is shut (which is what they do when they cut off your gas service).

That way you're at least not going to have the inside of your house fill with gas.

The trick with an overpressure gas main is that pulling that lever isn't going to be a "gas vents off for a few seconds and then things are good again" event. You won't be just reducing the pressure for your house, you'll be reducing the pressure for your entire neighbourhood, and there's going to be a pretty significant amount of gas that needs to vent.

Also, I'm not sure if this is the case with methane, but propane has a really fun property... Going from compressed/liquified propane to gas propane has a high enough latent heat of vaporization that it can cool the surrounding liquid enough to freeze it (!!!). There was a court case around here a few years ago with a propane truck that blew a valve and started venting propane to the atmosphere. The liquid->gas transition cooled off the valve so much that a solid propane plug formed and stopped the leak (-188 degC!). Temporarily, of course... the plug eventually thawed, the gas continued escaping, and things got bad again. Having devices that could experience similar behaviour installed at peoples' homes seems pretty dangerous to me.

It's all a shitty situation. Really, this is on the gas company. Their pumps should have never gotten the lines pressurized like this, and they should have had mechanisms in place to vent it in a controlled and safe fashion.

There are lots of such safeties in the system, it's just that unlike electricity an 'open' connection in a gas line is called a leak... So the problem is much harder, and there is no safe configuration where you can force a valve to shut down in a passive way if the other side is not playing nice. Above a certain pressure anything will go and to design for even higher pressures would be cost prohibitive. So burst plates and other non-resettable safety devices are deployed in strategic locations, and their default mode is to vent.

What exactly went wrong here is still unknown but the smart money is on an uncontained overpressure and a failure of one or more safeties. All it takes i the right set of circumstances. For instance: a very short pulse of very high pressure followed by a lower pressure not high enough to cause venting to occur. That would do nicely: every membrane in the line that was at or near the end of their service life would break causing high pressure to end up on the low pressure side but it would not cause the main safeties to trip.

Keep in mind that all this stuff is passive, mostly mechanical and in many cases decades old.

Something similar can happen to circuit breakers: there is an effect that causes the breaker to weld itself into position rather than to break the circuit, and there are plenty of examples of the breakers themselves catching fire due to high resistance between the breaker contacts. Then there is lightning, which can zap your house to the point that your electronics gear is nicely plated on the inside of empty casings and the breakers are all still sitting there as if everything is fine.

It is super hard to create a safety system that will always work under every circumstance, especially if you want to do this maintenance free. More so, if you did not design it maintenance free but someone decided to skip on the maintenance.

Tell me about it. In 2007, there has been a bridge collapse[0] that was mostly caused by inadequate maintenance. Two others (more recently) were accidents[1][2]. And these weren't some little bridges in the middle of nowhere. They were heavily used interstates (sometimes crossing rivers). You can't miss them.

I live in a city that has three major rivers in it, and more bridges than any other[3]. Things like these give me the willies.

I used to live in Andover, MA in a prior existence, and while the town is very rich it is also as they say, very historic. I wouldn’t be shocked if the infrastructure was ancient. As for Lawrence (disclaimer: it may have changed) it was a seriously poor former mill town, and I wouldn’t be shocked if their infrastructure and services were in awful shape.

This is just bad infrastructure design. The gas line grid should have a safety vent that blows open in an abandoned field at some pressure between the operating pressure of the line and the maximum pressure the houses can handle.

Natural gas infrastructure in New England and MA in particular is horrible. A big part of the reason why prices remain high (3-4x vs New York) in the region despite the recent fracking boom. Incidents such as this do not help.

That idea has been floating around a lot. It's definitely not outside the realm of possibility, though what makes me think is was human error is the fact that Columbia Gas (company responsible for those lines) publicly announced work on the lines about a week before this happened.

By close of business Friday the plumbing lobby will be saying this is because people did their own gas lines and requesting laws to drive them even more business. They'll probably get it too. By Monday everyone will have forgotten. Maybe there's be some hand wringing and an investigation. Not an extra cent will be allocated to fixing the infrastructure or processes that failed and led to this. That's how things work in this state, but hey, at least there's a few high paying jobs in Boston and we have progressive politics so we'll just keep patting ourselves on the back about how great it is to live here.

But the failsafes are not. Overpressure is something the system is designed to handle, and those gas substations that you see every now and then in fields are the places where the overpressure regulation devices are located, and they are purely mechanical.

> It'd be shocking if a software failure could cause dozens of fires.

It would be, but this isn't that. The actuators on these systems are made with the express purpose that line fluctuations will always be slow enough to catch up with. But if a regulator fails in a bad way that might cause a prolonged overpressure with the initial change arriving as a spike, which may expose further weaknesses downstream.

So the signature of an upstream regulator failure (a big one, and a sudden one too), is fairly consistent with what you are seeing here. The software actuators would not cause a pressure rise fast enough for that initial spike and the limit settings on those actuators (which are mechanical) would not allow those actuators to move beyond certain minimum and maximum set points for each line that they service.

The people that designed these systems were anything but stupid and it is failsafes layered on more failsafes, the big killer for systems like this is a very simple one: back maintenance.

I'd speculate that the simplest root cause might be an system overpressure. Any hookup to a valve that couldn't contain a pressure of some level could be susceptible to leaking gas onto an ignition source which could then start a fire.

It’s peculiar to me that you have repeatedly attempted to create a rumor that it was hackers even though there is no evidence to support that. Are you playing at something or just enjoy spreading misinformation?

What seems strange is IF someone had root on a enemy nation's natgas distribution plant, a short spike resulting in a handful of explosions is the third least effective attack I can think of (the least being doing nothing, second least effective being some kind of blackmail attempt). Performing almost any other conscious action would be more destructive to life and property and economy. Therefore unless its literally accidental (like the SQL slammer attack decades ago causing DOS via flooding) there almost certainly can not be hacking / terror involvement.

Yet its also too destructive and attention seeking to be a plausible threat or sending a message; if outsiders messed with the SCADA to do this, fifteen minutes later all the passwords would be changed and sites physically locked down, such that a threat to do something more destructive next time (or else..) such as flicking the gas supply off for a couple minutes would be a non-starter. You have to look at it militarily like a stealth attack; giving away your position is not a wise first move if your whole strategy is stealth. You get one shot and this would be an intentional miss, so ...

This would also imply its not an inside job; an insider would know that in my state (admittedly not MA, thankfully) an interruption in pressure requires an attempt at physical access by a rep with a leak sensor to verify pilot light and pilot light safety interlock for EVERY point of use and/or door tag notification warnings. Its happened to me a couple of times for some street work replacing pipes and replacement of my old meter. Its kind of an expensive labor job, a wealth transfer from the company to the union. The fact this didn't happen kind of exonerates the union.

So rule out outsiders and insiders. A nutjob would probably drive a truck into an above ground facility, or frankly, just drive into people, so its probably not a nut. Not many options left. Space aliens did it accidentally? Maybe they closed down that solar observatory in NM because the space aliens are coming to mess with our delicious natgas.

You'd hope that there'd be mechanical, non-hackable safeguards in place to prevent obvious over-pressure situations. Why would any part of the system allow a serious over-pressure that would result in catastrophe like this?

There are, but one of their safety mechanism is that excess pressure will lead to venting and that in turn can lead to fire if it happens enough. A tiny bit of venting is harmless but a lot of it over a short period of time can cause dangerous concentrations of gas mixed in with regular air, and that is a very nicely combustible mix.

LOL SCADA? You haven’t been involved with infrastructure in MASS have you?

Let’s put it this way: it wouldn’t surprise me, especially in Lawrence, if some of the gas mains were still made out of wood. Before you scoff, NYC replaced the last wood gas main that they knew of 25 years ago, but they still occasionally find wooden pipe in their systems.

The best way I’ve heard the gas infrastructure described is “antiquated ... if it was aged, it could be updated and replaced, but it’s so antiquated all that can be done is patchwork because there’s no time to do anything but.”

You're just changing infrastructure attack to industrial espionage. You calling it something else doesn't detract from the point that it's been done, and it was targeted at one country or another's infrastructure.

Nukes don't deter infrastructure attacks. They ENCOURAGE them. Cripple your opponents ability to maintain his arsenal and coordinate his forces, and you could shift the odds of pulling off a crippling first strike immensely.